No, there have been serious scientific discussions of what would happen to the earth without a moon, and the Earth would simply wobble beyond all control. The equator would flip flop between being the new polar regions and back again, and life as we know it would never be able to survive.
-----------------------------------------------------------------------------------That sounds like pseudoscience to me. Link?
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As I recall this was strongly suggested on A Nova science program called our lone wonderful moon or words to that effect. And that without a moon we would have no stability about our axis, and therefore changes in climate would occur far faster than plants and many animals could adapt to changes.
I did also try a google search, but found a few similar but more superficial links.
It's true. The moons gravity is what keeps our axis stable. Sure the sun has a much higher gravity but it's much further away than the moon so the moon has the higher gravitational pull on us than the sun.As for the earth precessing, that seems unlikely. The moon is not keeping us from wobbling. i really cannot see how having a second item spinning around you will stop you from tipping or shaking...
Yep, the moon acts together with the water in the ocean's on earth as a flywheel for earth.
There is one thing i never understood.
When the moon is on the opposite side of the earth, it causes almost the same spring tide as when the moon is at the same side of the earth as the sun is. I would expected it to be stronger...
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OH... the moon pulls the earth away from the water on the opposite side. Why has no one ever explained this before Howstuffworks?
http://science.howstuffworks.com/environmental/earth/geophysics/tide-cause.htm
Center of gravity maybe?
The mass center is still the same no matter how much you are pulling the water away. It may be a rotational moment of inertia problem.
I am disappointed with that video in that they discuss the sudden disappearance of the moon. I think it would have been more interesting if the discussion had at least included the scenario of the moon never existing ... or even a much smaller one. For the moon to suddenly disappear there would obviously have to be a cataclysmic collision of the moon and some pretty massive and/or fast moving asteroid. Earth, having the front row seat, would clearly experience far more immediate effects from this collision & the washing of giant waves, tho extreme, would be secondary.Mars does have huge tilts on it's axis varying from 15 degrees on the low and 75 degrees on the high side. The moon locks our axis in at 23 degrees. That's why we have stable climates. If there wasn't a moon the other planets and our sun's gravity would cause our axis to tilt wildly. Extreme climate changes would follow. If it just disappeared suddenly we'd have a global tsunami as well as the water would rush towards the gravity of the sun. Watch the show The Universe season 4 episode 2 "The day the moon was gone." You can stream it instantly on Netflix. They talk to scientists from major universities and astrophysicists as well. This is what they say not me.
this is a tough concept for many people to grasp...that's OK. i'll try to put it in layman's terms as best i can. the fact that the force of gravity changes with distance gives rise to the term "tidal" force. that is, tidal forces are really just differences in the force of gravity between one location and another. clearly the oceans facing the moon have a greater gravitational bond with the moon than the oceans on the side of the earth opposite the moon. while howstuffworks.com's explanation of the bulge on the opposite side of the earth isn't totally incorrect, IMO its a pretty poor explanation. the bottom line is that the moon pulls harder on everything closer to it (the oceans, the mountains, and the entire earth itself for that matter) than it pulls on anything that's farther away from it. that is, as you get progressively further away from the moon, so does its gravitational force on you get progressively weaker. hence the tidal force's ability to "stretch" things out along the axis of force (in this case, the force of gravity).I still don't understand how the moon can cause a high tide on the opposite side of where it's on. No textbook has ever explained that, only showed this same stupid picture.![]()
this is a tough concept for many people to grasp...that's OK. i'll try to put it in layman's terms as best i can. the fact that the force of gravity changes with distance gives rise to the term "tidal" force. that is, tidal forces are really just differences in the force of gravity between one location and another. clearly the oceans facing the moon have a greater gravitational bond with the moon than the oceans on the side of the earth opposite the moon. while howstuffworks.com's explanation of the bulge on the opposite side of the earth isn't totally incorrect, IMO its a pretty poor explanation. the bottom line is that the moon pulls harder on everything closer to it (the oceans, the mountains, and the entire earth itself for that matter) than it pulls on anything that's farther away from it. that is, as you get progressively further away from the moon, so does its gravitational force on you get progressively weaker. hence the tidal force's ability to "stretch" things out along the axis of force (in this case, the force of gravity).
another example that helps alot in visualizing this concept is a body in the vicinity of a black hole, particularly a stellar mass black hole (as opposed to the super-massive black holes found at the centers of galaxies...but that's neither here nor there). black holes are known for their very disruptive tidal forces b/c their gravity is so strong. let us suppose you're falling toward a black hole feet first from very far away. you would not be able to notice the difference in the amount of gravity of the BH exerts at 10 billion miles out versus 9.9billion miles out for example. and yet during that time, you'll have fallen 100 million miles closer to the black hole - that's a long way to travel toward a massive object and not feel the change in gravitational force. but the closer you get to the BH, the greater its gravitational force becomes. eventually you'd get close enough to the BH to where the difference between the gravitation force pulling on your feet is significantly greater than the gravitational force pulling on your head. this is "tidal forces 101," and the closer you get to the BH, the greater the tidal forces become (and the greater the difference between the gravitational pull on your feet vs your head becomes). you will eventually get stretched out along the axis of force, and your feet will accelerate toward the BH at a greater rate than your head, stretching you out like a piece of spaghetti.
so that is why there is high tide on opposite sides of the earth at any given time. that is, the above explanation is why the earth (along with its oceans, since they are fluid) takes on an elongated shape along the axis of gravitational pull. i can see how some folks still might be cofused as to why all the oceans don't just flow to the side of the earth nearest the moon, but it just doesn't work that way. tidal forces have the tendency to stretch things out along the axis of force, giving matter farthest from the source of gravity the appearance that it is being stretched in the opposite direction, when really its getting pulled in the same direction as everything else - just less so b/c it is farther from the source of gravity.
